It is often desirable to be able to lock a door in order to obtain privacy or protection. In some cases, a door may not have a lock installed or a lock which is operable. In other cases, such as where a key lock is installed, the lock may be suspect in its exclusiveness and added security may be desirable.
Portable door locks have been developed to provide privacy and protection in such cases. Prior art door locks are usually securable to a door jamb by hooking a tooth of an elongate base into the aperture present in the striker plate when a door is in an open position. As the door is closed, the door deflects a spring arm attached to the base and biased into the path of the door. When the door has passed the spring arm and is in the closed position, the bias returns the spring arm to its original position in the path of the door thus preventing the door from opening. To open the door, the spring arm is manually deflected out of the path of the door so that the door can be swung open. The lock can then be removed from the striker plate and kept in a pocket or a suitcase.
While this type of prior art lock obtains the necessary end result, there are some difficulties which need to be overcome. The first is that as the door deflects the spring arm, the door can become undesirably marked due to the force of the spring arm upon the door. Further, if the door lock is secured to the door jamb and then the door closed from outside of the room, the room becomes locked with no one to unlock the door and the door or a window may have to be broken to gain access to the room. Also with this type of door lock, it is inconvenient to unlock the door because as the spring arm is being manually deflected from the path of the swinging door, the fingers used for the operation are in a vulnerable position in the path of the opening door. This is especially dangerous if someone were to open the door from the outside.
Therefore, it is among the objects of the invention to provide an improved auxiliary door lock which overcomes the aforementioned difficulties.